PTL 1 discloses, as an engine valve control mechanism configured as mentioned above, a configuration provided with a hydraulic cylinder that drives the rocker shaft to rotate and in which a middle/high-speed rocker arm is fitted into an eccentric large-diameter portion of a rocker shaft. In this configuration, the middle/high-speed rocker arm is supported by the eccentric large-diameter portion of the rocker shaft via an eccentric bushing, the middle/high-speed rocker arm is entirely shifted by driving the rocker shaft to rotate so as to change the cam lift amount, and consequently a change of settings of the valve lift amount and the valve timing is realized.